Search results for "Spore"

Interaction of Human Phagocytes with Pigmentless Aspergillus Conidia

2000

ABSTRACT A defect in the pksP gene of Aspergillus fumigatus is associated with the loss of conidial pigmentation, a profound change of the conidial surface structure, and reduced virulence. The structural change of the conidial surface structure was not observed in similar A. nidulans wA mutants. Our data indicate that the pigment of both species is important for scavenging reactive oxygen species and for protection of conidia against oxidative damage.

A conspectus of and key to GreekIsoetes(Isoetaceae), based on a reassessment of Haussknecht's gatherings of 1885

2015

The three Isoetes species recorded from Thessalia (Thessaly) in N Greece by Haussknecht, in 1899, under the names I. setacea, I. heldreichii, and I. phrygia, were reassessed using megaspore and microspore ornamentation in addition to macromorphological features. “Isoetes setacea” is not the SW European I. delilei to which the name I. setacea was generally misapplied, nor “I. echinospora” as it has been called due to a misunderstanding, but a so far undescribed species here named I. haussknechtii; it has not been found again in Haussknecht’s locality but has recently turned up in Peloponnisos and the E Aegean Islands. I. heldreichii, described from Haussknecht’s gathering, is apparently exti…

STUDY ON ISOLATED MICROSPORE CULTURE IN CITRUS SINENSIS L. OSBECK CV. MORO, A BLOOD ORANGE CULTIVAR

2014

In vitro tissue culture represents a useful support for the advancement of Citrus breeding and propagation. Haploidy technology, that is the single-step development of complete homozygous genotypes from heterozygous parents through gametic embryogenesis, has already a huge impact on many relevant crops, representing an integral part in their breeding programmes (Germanà 2011a; 2011b). In order to increase the number of genotypes responding to gametic embryogenesis, in vitro isolated microspore culture of Citrus sinensis L. Osbeck cv. Moro, has been carried out, investigating the influence of the culture medium composition, and, particularly, of the plant growth regulator types and concentra…

Hymenopteran specificity of Bacillus thuringiensis strain PS86Q3

2008

Abstract The biological activity of Bacillus thuringiensis (Bt) strain PS86Q3 against five Hymenopteran species was determined by means of bioassays adapted to each species. Four species of sawfly that are important pests of conifers (Diprion pini, Gilpinia hercyniae and Pristiphora abietina) or ornamental plants (Arge rosae), as well as the non-target honeybee, Apis mellifera, were studied. Two out of the four sawfly species tested were found to be sensitive to PS86Q3 crystals or spore/crystal suspensions. A sporulated culture of this strain was moderately active on D. pini, and a complete bioassay with solubilized crystals was performed to estimate the LC50 of 4.9 mg/ml. Pristiphora abiet…

Development of multicellular pollen of Eriobotrya japonica Lindl. through anther culture

2006

8 pages, 5 figures.-- Printed version published Dec 2006.

Cloning and expression of genes involved in conidiation and surface properties of Penicillium camemberti grown in liquid and solid cultures.

2008

International audience; Based on bioinformatic data on model fungi, the rodA and wetA genes encoding, respectively, a RodA hydrophobin protein and the WetA protein involved in conidiation mechanisms, were PCR-cloned and characterized for the first time in Penicillium camemberti. These results, completed by a sequence of the brlA gene (available in GenBank), which encodes a major transcriptional regulator also involved in the conidiation mechanism, were used to compare, by qRT-PCR, the expression of the three genes in liquid and solid cultures in a synthetic medium. While expression of the brlA and wetA genes increased dramatically in both culture conditions after 4 days of growth, expressio…

CHARACTERISATION OF MICROSPORE EMBRYOGENESIS IN ANTHER CULTURE OF CITRUS.

2002

FIRST EMBRYONIC STAGES OF CITRUS MICROSPORE DERIVED EMBRYOS.

2002

Histidine kinases mediate differentiation, stress response, and pathogenicity in Magnaporthe oryzae.

2014

The aim of this study is a functional characterization of 10 putative histidine kinases (HIKs)-encoding genes in the phytopathogenic fungus Magnaporthe oryzae. Two HIKs were found to be required for pathogenicity in the fungus. It was found that the mutant strains ΔMohik5 and ΔMohik8 show abnormal conidial morphology and furthermore ΔMohik5 is unable to form appressoria. Both HIKs MoHik5p and MoHik8p appear to be essential for pathogenicity since the mutants fail to infect rice plants. MoSln1p and MoHik1p were previously reported to be components of the HOG pathway in M. oryzae. The ΔMosln1 mutant is more susceptible to salt stress compared to ΔMohik1, whereas ΔMohik1 appears to be stronger…

Coexistence of three microsporidia parasites in populations of the freshwater amphipod Gammarus roeseli: evidence for vertical transmission and posit…

2004

We investigated the prevalence, transmission mode and fitness effects of infections by obligatory intracellular, microsporidian parasites in the freshwater amphipod Gammarus roeseli. We found three different microsporidia species in this host, all using transovarial (vertical) transmission. All three coexist at different prevalences in two host populations, but bi-infected individuals were rarely found, suggesting no (or very little) horizontal transmission. It is predicted that vertically-transmitted parasites may exhibit sex-specific virulence in their hosts, or they may have either positive or neutral effects on host fitness. All three species differed in their transmission efficiency an…